The aim of the study is to evaluate the physicochemical (radiopacity, setting time, film thickness, flow, solubility, pH, calcium ion release and dental discoloration) and biological properties of an experimental Portland-based sealer containing different concentrations of radiopacifying agents zirconium oxide and calcium tungstate. The sealers will be divided into 6 groups: I - white MTA (control), II - white Portland cement (PC), III - PC with 20% zirconium oxide, IV - PC with 50% zirconium oxide, V - PC with 20% calcium tungstate, VI - PC with 50% calcium tungstate. Physical tests will be performed in accordance to ISO 6876/2001 and ASTM C266/2008 recommendations. To determine pH and calcium ion release, 10 acrylic teeth with simulated root canals will be used for each group. The teeth with sealers will be immersed in MiliQ water and the liquid analyzed after 3, 7 and 15 days. To evaluate dental discoloration 10 bovine teeth will be cleaned and obturated with the sealers. After 7, 15, 30 and 60 days teeth will be analyzed using a spectrophotometer. For biological analysis 108 Wistar rats will be divided into 6 groups. Two polyethylene tubes filled with the sealers will be implanted in each animal. After 15, 30 and 60 days the implants with surrounding tissues will be removed. The sections will be stained with hematoxilin and eosin and analyzed under light microscope. The results will be submitted to a preliminary test of D'Agostino and Pearson to verify the presence or absence of normal distribution (p<0.05).
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